I'm surprised nobody has come up yet with FlashDevelop. Probably in the top 2 of AS code editors. It's also free, the problem is it's Windows only.

Then, if you like Eclipse, there's another really good editor called FDT, but this one you have to pay for. From what people say it's totally worth the money, I don't use it simply because I don't like Eclipse and when I tried it in Linux it had various glitches here and there.

Email codedump link for IDE for developing in ActionScript (Flash). Any suggestions?